---
title: "APFS"
url: https://storagestudio.us/wiki/glossary-apfs
category: "Glossary"
tags: ["glossary", "external drive", "drive formats"]
summary: "APFS (Apple File System) is the format Macs use for their disks. It is the recommended format for the external drive you use with Storage Studio."
updated: 2026-10-01T05:35:50.000Z
---

# APFS

APFS (Apple File System) is the format Macs use for their disks. It is the recommended format for the external drive you use with Storage Studio.

**APFS** (Apple File System) is the format — the way files are organised on a disk — that Macs use for their built-in disks. It's what makes features such as [local snapshots](https://storagestudio.us/wiki/glossary-local-snapshot) possible.

APFS comes in two flavours. The usual one treats capital and small letters in names as the same (*Photo.jpg* and *photo.jpg* are one file); a *case-sensitive* variant treats them as different.

In Storage Studio:

- APFS is the recommended format for your [external drive](https://storagestudio.us/wiki/glossary-external-drive). **Mac OS Extended** is accepted too; [exFAT](https://storagestudio.us/wiki/glossary-exfat) needs you to confirm a warning.
- When you move an app, Storage Studio checks whether the drive and your Mac treat capital letters the same way. If the app holds files whose names would collide on the drive, it stops the move rather than lose one of them.

See also: [Drive formats: APFS, Mac OS Extended and exFAT](https://storagestudio.us/wiki/drive-formats) · [Choosing an external drive](https://storagestudio.us/wiki/choosing-an-external-drive)

## What links here

- [Access list (ACL)](https://storagestudio.us/wiki/glossary-access-list)
- [Drive formats: APFS, Mac OS Extended and exFAT](https://storagestudio.us/wiki/drive-formats)
- [Local snapshot](https://storagestudio.us/wiki/glossary-local-snapshot)
- [exFAT](https://storagestudio.us/wiki/glossary-exfat)